RE: how to use substring and charindex to extract desired string

ChrisM@Work

SSC Guru

Points: 186127

July 10, 2014 at 2:05 am

#1728291

SELECT

MyString,

x.p1, y.p2, z.p3,

LeftBitty = LEFT(MyString,NULLIF(z.p3,0)-1)

FROM (VALUES ('ek/df/cv/'), ('ek/df/cv/f'), ('ek/df/cvf')) d (MyString)

CROSS APPLY (SELECT p1 = CHARINDEX('/',MyString,0)) x

CROSS APPLY (SELECT p2 = CHARINDEX('/',MyString,p1+1)) y

CROSS APPLY (SELECT p3 = CHARINDEX('/',MyString,p2+1)) z

SELECT

MyString,

z.p3,

LeftBitty = LEFT(MyString,NULLIF(z.p3,0)-1)

FROM (VALUES ('ek/df/cv/'), ('ek/df/cv/f'), ('ek/df/cvf')) d (MyString)

CROSS APPLY (SELECT p3 = CHARINDEX('/',MyString,CHARINDEX('/',MyString,CHARINDEX('/',MyString,0)+1)+1)) z

^{“Write the query the simplest way. If through testing it becomes clear that the performance is inadequate, consider alternative query forms.” - Gail Shaw}

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